Barrel adjuster for the gear cable. Currently I'm using a gx rear mech which doesnt have an adjuster. Cables run along top tube so no adjuster there either.
I have no problems with the levers/spyres feel so not going to change the levers. Those wouldnt let me change gear anyway
inline barrier adjuster? doesn't it have that on the calipers?
Look into Cane Creek SCR-5, better cable pull with disc.